Congenital Hypothyroidism American Thyroid Association

Hashimoto’s disease, an autoimmune disorder, is one of the most common reasons for primary hypothyroidism in which the thyroid is buy synthroid attacked by its own body’s immune system interfering with the normal functioning of the thyroid hormones 1,12. It needs careful management as this abnormality can hinder mental development and may cause compressive goiter in infants. In morphological thyroid disorders, the problem is usually differentiated thyroid cancer, as its frequency of growth is higher during pregnancy. Its consequences are aggravated and enhanced by the thyroid-stimulating hormone (TSH), like the effect of the human chorionic gonadotropin (hCG) hormone 4,14. About 20 years ago, many endocrinologists brought the effects of maternal thyroid hormone deficiency to public attention 15. In 1999, it was demonstrated that a child’s neurodevelopment might be severely affected if hypothyroidism is left untreated in pregnant women 16.

• Thyroid autoantibodies can harm a pregnant individual and the fetus, as untreated hyperthyroidism and hypothyroidism in pregnancy pose risks to both mother and fetus.
• In these cases, Synthroid is prescribed to help manage the condition and restore normal thyroid function.
• Congenital hypothyroidism occurs when a newborn infant is born without the ability to make normal amounts of thyroid hormone.
• Data are often controversial because of different methods for assessing thyroid function, but a link is often described.

What are the signs and symptoms of congenital hypothyroidism?

Thyroid hormones are important for the intrauterine homeostasis of the fetus, and cooperate with the adrenal hormones during the perinatal period to determine a physiological adaptation to the extrauterine life (57). In the fetus, thyroid gland appears complete at weeks of gestational age (GA); blood levels of thyroxine (T4) and triiodothyronine (T3), which start to be measurable at that time, increase gradually during pregnancy (58). Fetal hypothalamic-pituitary-thyroid axis begins to work after the first trimester of pregnancy and its development appears complete at the end of gestation.

Some symptoms of hyperthyroidism may include palpitations, excessive sweating, heat intolerance, anxiety, insomnia, weight loss, and tremors. Physical examination findings may include tachycardia, lid lag, stare, diaphoresis, and hyperreflexia. Findings specific toGraves disease include diffuse goiter, ophthalmopathy (exophthalmos), and pretibial myxedema. See the American Academy of Pediatrics (AAP) policy statement, Update of Newborn Screening and Thereapy for Congenital Hypothyroidism, for more information.

Iodide is cleared from the kidneys when the maternal glomerular filtration rate increases. This clearance, together with enhanced thyroxine metabolism, leads to a drop in plasma iodide levels. Due to increased placental deiodinases, T4 metabolism is boosted in the second and third trimesters 2,26.

Fetal thyroid function: diagnosis and management of fetal thyroid disorders

• For women on thyroid hormone prior to conception, thyroid function testing should be performed regularly throughout pregnancy as it is very likely that the thyroid hormone dose will need to be increased.
• Detection and treatment of maternal hypothyroidism early in pregnancy may prevent the harmful effects of maternal hypothyroidism on the fetus.
• Maintaining stable thyroid hormone levels can lower the risk of miscarriage, preterm birth, and fetal growth restriction.
• If the mother is a known case of hypothyroidism throughout the pregnancy, then there is a very high risk of low-birth-weight babies being born 23.
• FT3 levels continue to increase during the first 28 days because of both increased levels of TSH and increased postnatal expression of deiodinase D1.

Hypothyroidism can occur due to various factors, including autoimmune diseases, radiation therapy, or surgical removal of the thyroid gland. In these cases, Synthroid is prescribed to help manage the condition and restore normal thyroid function. A severe, life-threatening form of hyperthyroidism, called thyroid storm, may complicate pregnancy. This is a condition in which there are extremely high levels of thyroid hormone that can cause high fever, dehydration, diarrhea, rapid and irregular heart rate, shock and death, if not treated.

Current evidence from several species indicates that there is substantial transfer of maternal thyroid hormones across the placenta. In addition to the potential risks to the pregnancy, thyroid disorders can also have long-term effects on the baby’s development. Studies have shown that children born to mothers with untreated thyroid disorders during pregnancy may have an increased risk of cognitive impairments and developmental delays. It may lead to preterm birth (before 37 weeks of pregnancy) and low birth weight for the baby.

Neonates Small for Gestational Age (SGA) and thyroid function

• Parents should crush up each day’s tablet, and then mix with a small volume (about 1 tsp) of liquid, either expressed breastmilk, water, or formula.
• Effective interprofessional communication is paramount, allowing seamless information exchange and collaborative decision-making among the team members.
• Synthroid is a synthetic form of the hormone thyroxine, which is produced by the thyroid gland.
• In general, side effects occur only if the dose is too high, which the endocrinologist can avoid by checking blood levels on a periodic basis.

These antibodies are immunoglobulin G proteins that can cross the placenta and cause fetal hyperthyroidism.21333In this special scenario, treatment with a block-and-replace strategy may be warranted. Subclinical hyperthyroidism, as well as gestational thyrotoxicosis, do not require treatment during pregnancy, and rather, observation is recommended with periodic monitoring of thyroid function tests every 4 to 6 weeks. In the last few years, the correlation between maternal thyroid dysfunction during pregnancy and adverse obstetric and perinatal outcomes has been largely investigated.

Because fetal growth and birth weight Z-score already accounted for gestational age and gender, we didn`t adjusted for those variables in the analyses. By taking Synthroid, pregnant women with hypothyroidism can ensure that their thyroid hormone levels remain within the optimal range. This is important because inadequate thyroid hormone levels can interfere with the baby’s brain development and growth.

Find research studies

For this reason, thyroid dysfunction is a common condition in preterm infants and can be linked to several factors. First, there are physiological conditions related to prematurity, that include immaturity of the hypothalamic-pituitary-thyroid axis, impairment of thyroid ability to concentrate and synthesize iodine, and immaturity of the metabolic pathways in the thyroid. Then, preterm newborns have greater demand for thyroid hormones for thermogenesis and dealing with diseases related to prematurity. Williams et al showed that typical diseases of preterm, e.g. respiratory distress syndrome (RDS), sepsis, intra ventricular hemorrhage (IVH), may alter thyroid function through inflammatory response.

Data Availability Statement

During pregnancy, the placenta is critical in reacting to and regulating the mother’s thyroid hormones 27. These alterations in levels of hormones induce changes in the size of the thyroid gland, which eventually reverts to its previous size after the baby is delivered. As a result, the measures used to assess hypothyroidism throughout pregnancy vary depending on the trimester and the remainder of the pregnancy 2,26. Iodine inflow is assumed to be controlled by the sodium/iodine symporter (NIS), whereas outflow is controlled by pendrin 11,29.